Introduction to Sulphuric Acid

Q. Compound ‘X’ decomposes to form compound ‘Y’ and CO₂
gas.
Compound Y is used in manufacturing of cement.
(a) Name the compounds ‘X’ and ‘Y’.
(b) Write the chemical equation for this reaction.

Q.

Ba(OH)₂ + 2NH₄Cl ---------> BaCl₂ + 2NH₄OH

Is the above-mentioned chemical reaction correct?

Q. On reaction with sulphuric acid, the copper sulphate crystals turn .

1. blue
2. red
3. white
4. yellow

Q.

State what you will observe when ammonium hydroxide solution is added to copper sulphate in excess.

Q. Give the equation for the preparation of each of the following salts from the starting material given.
(i) Copper sulphate from copper (II) oxide,
(ii) Iron (III) chloride from Iron.
(iii) Potassium sulphate from potassium hydroxide solution.
(iv) Lead chloride from lead carbonate (two equations).

Q. (a) The diagram given below is to prepare iron (III) chloride in the laboratory:
Figure

(i) What is substance B?
(ii) What is the purpose of B?
(iii) Why is iron (III) chloride to be stored in a closed container?
(iv) Write the equation for the reaction between iron and chloride.
(b) Write the equation(s) for the reaction(s) to prepare lead sulphate from lead carbonate.

Q.

Explain, why silver nitrate crystals are dissolved in distilled water and not in tap water to prepare silver nitrate solution as a laboratory reagent.
Give one chemical test to distinguish between dilute hydrochloric acid and dilute sulphuric acid.

Q.

(i) How will you distinguish between dilute H₂SO₄ and conc H₂SO₄?
(ii) How will you distinguish between conc. HCl and conc. H₂SO₄?
(iii) Give main differences between drying agent and dehydrating agent.

Q. 20.0 gram of magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0 gram magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample? 1) 60 2) 84 3) 75 4) 96

Q. Common salt is prepared from the neutralisation reaction of hydrochloric acid and sodium hydroxide.

1. True
2. False

Q.

Write the equations for the laboratory preparation of the following salts, using sulphuric acid.
(i) Iron (II) sulphate from iron.
(ii) Copper sulphate from copper.
(iii) Lead sulphate from lead nitrate.
(iv) Sodium sulphate from sodium carbonate.

Q. During a thunderstorm, the rainwater contains nitric acid. The nitric acid is formed as a result of three chemical reactions. Describe or write balanced chemical equation for these three reactions.

Q. Answer the questions below, relating your answers only to salts in the following list:
sodium chloride, anhydrous calcium chloride, copper sulphate-5-water.
(i) What is the name given to the water in the compound copper sulphate-5-water?
(ii) If copper sulphate-5-water is heated, the water is driven off leaving anhydrous copper sulphate. What is the colour of anhydrous copper sulphate?
(iii) By what means, other than heating, can you dehydrate copper sulphate-5-water and obtain anhydrous copper sulphate?
(iv) Which one of the salts in the given list is deliquescent?

Q.

What kind of reaction is slaking of lime?

Q. Write equations to show the reaction between the following:
(i) copper and concentrated nitric acid
(ii) copper oxide and dilute nitric acid

Q.

What is the colour of pure sulphuric acid?

1. Blue

2. White

3. Green

4. Colourless

Q. Complete the following equation:
${\mathrm{FeSO}}_4.7H_{2}O\left(s\right)\stackrel{\Delta }{\to }\mathrm{FeO}(\mathrm{s)}+$+$7H_{2}O\left(g\right)$

1. ${\mathrm{SO}}_3$
2. ${\mathrm{SO}}_2$
3. ${\mathrm{FeSO}}_4$

Q.

(a) What must be added to sodium chloride to prepare hydrogen chloride?
(b) Write the equation for the reaction which takes place in question (a).
(c) What will you observe, when hydrogen chloride mixes with ammonia?

Q.

What happens when crystals of Blue vitriol are added to the beaker containing concentrated ${\mathrm{H}}_2{\mathrm{SO}}_4$? Explain the observation.

Q.

State your observations when sodium hydroxide is added to the following solution slowly, until in excess : Copper chloride

Q.

What do you see when concentrated sulphuric acid is added to copper sulphate 5-water?

1. Blue crystals changes to blue powder

2. Blue crystals changes to white powder

3. Blue crystals changes to green powder

4. Blue powder changes to blue crystals

5. Blue powder changes to white crystals

Q. An organic compound C(molecular formula C2 H4 O2) reacts with sodium metal to form a compound B and evolves a gas which burns with a pop sound.Compound C on treatment with an alcohol A in presence of an acid forms a sweet smelling compound S(molecular formula C4 H8 O2).On addition of sodium hydroxide to C it also gives B and water.S on treatment with Sodium Hydroxide solution gives back B and A.
Identify A, B, C and and write chemical equation for all the four reactions involved.

Q. Describe all what you will observe and write chemical equations, when limited amount of ammonia gas is passed through the following aqueous solution:
(i) ZnCl₂
(ii) FeSO₄
(iii) FeCl₃
(iv) Pb(NO₃)₂
(v) CuSO₄
(vi) CrCl₃.

Q. Write equations for the laboratory preparation of the following salts, using sulphuric acid:
(i) iron (II) sulphate from the iron.
(ii) copper sulphate from copper.
(iii) lead sulphate from lead nitrate.
(iv) sodium sulphate from sodium carbonate.

Q. rewrite the correct statments with missing words:
Copper sulphate crystals are dehydrated by sulphuric acid.

Q.

In this question, you are required to supply the word (or words) that will make the sentence correct. Rewrite the correct statement.
Copper sulphate crystals are dehydrated by sulphuric acid.

Q. (a) Explain with the help of a balanced equation, the brown ring test for nitric acid.
(b) Why is freshly prepared ferrous sulphate solution used in the ring test?
(c) Brown ring disappears if the test tube is disturbed.

Q.

Take a long magnesium ribbon. Clean it well by scraping it with a knife. Cut the magnesium ribbon into small pieces which are less than half a centimeter long. Put one piece of this magnesium ribbon carefully into 5 mL dilute hydrochloric acid taken in a test tube. Write the observation.

Experiment-2

Take 1 mL of acid in the test tube.Put the pieces of magnesium one by one into this.What may be the reason?

Q. The figure given below illustrates the apparatus used in the laboratory preparation of nitric acid:


(i) Name A (a liquid), B (a solid) and C (a liquid).
(ii) Write the balanced chemical equation to show how nitric acid undergoes decomposition.
(iii) Write the balanced chemical equation for the reaction in which copper is oxidised by concentrated nitric acid.

Q.

What would you see, when a crystal of CuSO₄.5H₂O is placed in concentrated sulphuric acid? Give reason to explain your observation.